toggle_repeat

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already indicate destructiveHint:false, so the description doesn't need to cover that. It adds the return behavior (an object with the new repeat state), which is useful but does not disclose any other side effects or context (e.g., whether it affects playback). Given the simplicity of the operation, this is adequate but not exhaustive.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is extremely concise: two short sentences that lead with the action and follow with the return value. There is no filler or redundant information, earning full marks for efficiency.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple toggling tool with no parameters and no output schema, the description provides enough information: what it does and what it returns. It doesn't mention any potential side effects on the transport system, but given the sibling tools and the operation's simplicity, it is nearly complete. A 5 would require explicit handling of edge cases or more detailed return structure, which isn't necessary here.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has zero parameters, so there is nothing to document. Per the calibration, a zero-parameter tool gets a baseline of 4. The description adds no parameter information because none is needed, and the schema is fully covered by the absence of parameters.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states 'Toggle repeat/loop mode' with a specific verb and resource. It distinguishes from the sibling tool 'get_repeat_state' by indicating a change operation rather than a read operation, making the intent unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The usage context is implied: it toggles, while 'get_repeat_state' reads. However, there is no explicit guidance such as 'use this to change repeat mode, use get_repeat_state to query it.' The description does not mention alternatives or exclusions, so it relies on the tool's name and sibling set for context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.